The Declaration summarized the colonists’ motivations for seeking independence. By declaring themselves an independent nation, the American colonists were able to confirm an official alliance with the Government of France and obtain French assistance in the war against Great Britain. So basically so it could be official
To contain communism, thinking was Vietnam went comunist it would spread more globally.
2 and 4
I think it because if you know what to say if you were there
John Marshall established the role of the Supreme Court in judicial review
